Tosxicology& Environmental& Industrial Agents ENV\'S 320 Final Exam 19 What is t
ID: 272277 • Letter: T
Question
Tosxicology& Environmental& Industrial Agents ENV'S 320 Final Exam 19 What is the most common cause of skin cancer in the U.S b) high fat die c) smcking ) coal mning 20 Which of the following statements is False ) Of all occupational skin disease, contact dermatitis accounts for over 90 percent of reported causes b) Allergic contact dermatitis represents a delayed hypersensitivity reaction c) Allergic contact dermatitis is a nonimmune related response caused by the direct action of an agent on the skin 4) Clloracne, one of the most disfiguring forms of acne n humans, is caused by exposure to halogenated aromatic hydrocarboms 21. The phases of Allergic dermatisitis from the First phase to the last one are: a) Induction, refractory period,, eliciting phase and persistence b) Refractory periods, eliciting phase, induction and persistence c)Refractory period, induction, eliciting phase and persistence 4) Persistence, eliciting phase, refractory period and induction 22 Which of the following statements is true? a) Langehass cells, which are always associated with the basal membrane, serves an important immunological b) Langerhans cells serve an immunological function because of the affinit c) Langorhans 'cells are normally associated y to phospholipids to which they attach with the dermis but do not serve immunological functions. Langerhans cells are normally associated with the epidermis and they migrate 23. Which of the following statements is true? a)Theden s superficial tothe epidermis. b) There are no blood vessels in the epidermis c) The epidermis peovides the structural strength of skin d Sweat glands in the epidermis 24. Wias negards to allergic cootact dermatitis which of the following is true? ?) The ment of repose is always dse dependent. b) The extens of the response is gencrally not dose dependent c) Allergic contact dermatitis 4) Allergic contact dermatitis is usually not associated with erythema (redness). is more common than irritant contact dermatitis 25. Which of the following is not true regarding the skin: a) a is an important route of exposure b) the thickness is not the same over the entire body c) to prodace a systemic effect a chemical must reach the dermis d) it is a good barrier to lipophilic compounds 26. Which of the following biological factors affecting percutancous absorption ?) Condron ofthe skin b) Anatomical site c) Sin age d) All of the above 27. The source of all keratinocytes is the a) stratum basale d) stratum spinosumExplanation / Answer
24. Ans- b. the extent of the response is generally not dose dependent
Explanation:
Contact dermatitis is a form of inflammation that occurs in the skin. It is of two types
a.allergic contact dermatitis – exposure to allergens
b. irritant contact dermatitis- exposure to irritants.
Allergic contact dermatitis is characterized by erythema or ‘redness’, swelling and vesicles in the acute phase. Allergic contact dermatitis reaction appears 207 days after exposure to allergens and is not dose dependent.
Irritant contact dermatitis is the most common type and is a dose-dependent.
25. Ans-d. it is a good barrier to lipophilic compounds
Explanation:
The skin is a route of exposure and its thickness vary all over the body. Most of the body the thickness of skin is around 2mm while on our eyelids it is only 0.5mm. It is a nonporous barrier of entry of most chemicals. Skin produces a detrimental systemic effect after absorption of chemicals.
26. Ans- d. all of the above
Explanation:
The factors affecting the Percutaneous absorption include:
a. Anatomical site
b. Skin-related factors like blood flow, pH, skin thickness, hair and pore density, and the content and structure of proteins, glycosaminoglycans (GAGs), water, and lipids
c. Barrier function
d. Metabolism
e. Hydration
27.Ans- a. stratum basale
Explanation:
A keratinocyte is a predominant cell that manufactures and stores keratin protein. The source of keratinocytes is the stratum basale of the skin.